Difficult to rein in, construction dust a major air polluter in Delhi
HT looks at sources of pollution other than private vehicles that must be controlled to clean Delhi’s toxic air. Studies show dust is the biggest polluter.delhi Updated: May 03, 2016 10:16 IST
A plume of dust rises up from a house under construction as a steady breeze blows. Construction workers at the site and passersby break into a fit of coughs. The latter hurriedly walk away.
The scene could be from any neighbourhood – big or small – in the city. Construction dust is among the big air polluters in the Capital, but measures to rein it in are woefully inadequate.
Dust is the biggest component of air pollution in the city, says an IIT Kanpur study. Of the total Particulate Matter 10 (PM 10) concentration in the city, 56% is caused by road dust. Dust is also source for 38% of the finer PM 2.5 load.
The National Green Tribunal (NGT) ruled last year that every builder and owner will have to cover construction sites using tarpaulin sheets to prevent construction dust from spreading. The order was passed to ensure compliance of the environment ministry’s construction guidelines.
The municipal bodies have since been slapping fines on builders and owners for not adhering. So far 1,447 of them have been fined.
But monitoring construction sites is a gargantuan task in a vast city like Delhi with numerous construction sites – big and small, authorised and unauthorised.
Delhi corporations clear 300 building plans every month. Additionally, construction is carried out on plots smaller than 105 square metres, which don’t require approval as per the unified bylaws. And construction in unauthorised colonies is not regulated.
A research paper released by the Johns Hopkins Bloomberg School of Public Health in November 2015 says higher levels of coarse particles in the air was leading to an increase in cardiovascular-related hospital stay for people 65 years and older in the US.
The researchers said this by far the strongest evidence to show that coarse particulate matter (sized 2.5 to 10 microns in diameter) released into the air from construction projects among other things were dangerous to humans.
The US has stricter implementation of laws that ban construction without covering the area. In India, the implementation is very low.
Health experts say that if a person is constantly exposed to dust and construction waste, he or she runs the risk of inhaling silica which escapes the filter mechanism of the nose and the throat. This reduces lung capacity and makes the person vulnerable to diseases such as tuberculosis and other respiratory and cardiovascular problems.
The Delhi government started vacuum -cleaning of roads in April as a pilot project. The concept, implemented in NDMC areas as well as several countries, says that vacuum cleaning will help clear the roads of dust instead of redistributing it.
PWD officials, however, say they encounter problems because the roads are not level. “The machines do not work effectively if the road is not level. We have to think about how the project will be expanded and made more effective,” said a PWD official who did not want to be named.
NDMC also encountered similar problems and levelled roads under its jurisdiction.